The present invention relates to an ink cartridge for supplying ink, under a proper negative pressure state, to a recording head ejecting ink drops in response to printing signals.
A recording device, in which an ink container is mounted detachably in a carriage having an ink jet recording head, has a retaining mechanism that prevents removal or shifting of the cartridge due to motion of the carriage during printing operation, and that enables easy disengagement of the cartridge by an external operation.
For example, as disclosed in JP-A-10-44451, such a retaining mechanism is structured so that a protrusion portion to be engaged with an ink cartridge holder is formed on a first surface of opposite side surfaces of an ink tank, while a pawl is formed on a pivotable lever on a second surface. When the protrusion portion is brought into engagement with the ink cartridge holder, the pawl is brought into engagement with the ink cartridge holder by moving the other surface through rotation about the protrusion portion.
However, such a retaining mechanism, which mounts the ink cartridge by rotation of the cartridge, is difficult to employ in an ink container which forms an ink flow passage via an ink supply needle communicating with a recording head.
That is, because the ink supply needle has a predetermined length for ensuring reliable communication with the ink container, there is a danger that the ink supply needle may be bent or damaged when it is subjected to an external force in a direction other than the axial direction, such as rotation in the manner just described. Accordingly, the ink container has to be moved parallel to the longitudinal direction of the ink supply needle.
Further, as disclosed in JP-A-9-11500, an ink cartridge is proposed that has two elastically deformable levers respectively formed on two opposite surfaces of a container storing ink therein, each lever having a pawl for engagement with an ink cartridge holder, so as to enable insertion of the ink cartridge onto the ink supply needle.
Furthermore, as disclosed in JP-A-2001-105587, there is proposed an ink cartridge in the form of a thin and rectangular parallelepiped container for storing ink and having a latch member on a front-surface-side wall in the longitudinal direction, and protrusions for guiding the insertion of the cartridge that are formed on opposite walls in the vicinity of the front-surface-side wall.
However, an ink cartridge having a memory device that stores information concerning the ink cartridge or the like requires reliable connection to minute electrodes, and thus must be reliably positioned.